KECENT COSMOGONIES 247 



adopted is by assuming that bodies thus mutually at- 

 tracted cannot fall to each other, but must arbitrarily ro- 

 tate around their common center of gravity. 



Now, we cannot allow Professor Bickerton to blow 

 hot and cold at once ; he must in duty bound stick to the 

 precepts he ostensibly professes, or frankly disavow 

 them. That he believes in the reality of proper motions 

 as arbitrary entities he explicitly states, and I think we 

 have no reason to infer aught else than that he regards 

 these conventionally as both inherent and random. In 

 other words, his postulated collisions are not to be con- 

 strued as arising from the mating stars seeking each 

 other out by virtue of their gravitational affinity, but 

 purely and simply by Uind chance. With this important 

 consideration ever in mind, let us weigh the probabilities 

 of such a collision coming to pass in our immediate zone 

 of the heavens of which alone do we know enough to 

 speak with reasonable confidence. 



The star nearest to our sun is Alpha Centauri, and it 

 is 26,000,000 million miles distant ; the next nearest is al- 

 most twice as far away. Now, by premiss, both Alpha 

 and the sun, in the absence of the ascertained facts, might 

 be moving haphazardly in any direction whatsoever, to- 

 ward, or away, or parallel, with reference to each other. 

 We will, however, prescribe such a movement on the part 

 of both that shall make it possible for them to collide. 

 Imagine, then, a straight line joining the two, and exactly 

 at the middle thereof, and at right angles therewith, a 

 circular diaphragm having a diameter exactly equal to 

 said line of joinder. We will now stipulate, to begin with, 

 that both Alpha and the sun shall possess proper motions 

 which will cause them to impinge simultaneously on the 

 diaphragm, but we will leave to chance just where each 

 shall pierce it. 



By thus conditioning the sun to strike within the area 

 of the diaphragm, we have arbitrarily restricted him to a 

 little less than one-seventh of his original liberty of 

 movement, and so, too, with the star. By restricting 

 both, however, at the same time we enhance the chances 



